Spectroscopic evidence for passivation of the La1.85Sr0.15CuO4 surface with gold

Abstract
High‐resolution x‐ray photoemission and inverse photoemission have been used to study the microscopic formation of Au overlayers on the high Tc superconductor La1.85Sr0.15CuO4. Our results indicate that Au does not induce disruption or surface reaction, unlike the reactive transition metals. The electronic states of the superconductor are attenuated as the Au overlayer covers the surface. We conclude that Au is a promising material for metallization and for passivation.